In the prior art systems for the purpose heat transport have been disclosed, including those in the following U.S. Pat. Nos.:
2,068,549 to D. B. Knight, 1-19-37, disclosing intermittent return of liquid condensate using a combination of vapor pressure and gravity flow; PA1 2,230,917 to P. G. Triana, 2-4-41, disclosing lifting liquids by solar heat using pressure of gas vaporized and reabsorbed; PA1 3,298,431 to E. A. Weaver, 1-17-67, disclosing return to condensate by gravity flow; and PA1 3,390,672 to C. D. Snelling, 7-2-68, disclosing returning condenste by pump or gravity-flow in a solar heating device.
In addition, textbooks deal with well known aspects of the art.
The present method in general use for transporting heat from an available source to a point of use, as in solar heating systems, is to circulate a sensible heat carrying medium such as air, water, a chemical compound, or the like, which is heated at the source, pumped to the point of use where the heat is extracted, and returned to the source to repeat the process. The most significant drawback to this method is the consumption of energy from an external utility source to pump the circulating fluid. There is a need for a method to transport heat energy using the same energy that is available at the source to power the system. The sensible heat carrying type media have the disadvantage of small heat carrying capacity per pound of fluid circulated. There is a need for a latent heat carrying type medium which will transport forty to fifty times more heat per pound in circulation, allowing systems to be made more compact and lighter in weight. Water is a widely used medium for the transport of heat, but when subjected to low temperatures must be mixed with anti-freeze to prevent freezing. The anti-freeze must be periodically replaced, and is troublesome and costly. There is a need for a medium which will not be affected at below-zero conditions. Media which are circulated in vented and open systems are subject to the entrance of dirt and other contaminants including atmospheric gases which promote oxidation of the internal parts of the system. There is a need for a completely sealed system. In general, there is a need for a more efficient method to transport heat energy from the available source locations where it is seated to those locations where the heat energy can be put to use, conserving energy and at the same time eliminating many of the disadvantages in present practices.